We are applying for the funds to purchase a much needed instrument, a Transmission Electron Microscope with the capabilities for distortion free imaging and high accelerating voltage for high contrast high magnification transmission electron microscopy. Utilizing immunoelectron microscopy and transmission electron microscopy aided morphometry of hearts, lungs and isolated cells we hope to gain new and useful information in the immunobiological reactions in the lung in response to oxygen toxicity, C5a induced inflammation and in hypertensive heart diseases. By utilizing immunoelectron microscopy we plan to study at molecular levels the assemblies of C5 convertase in the lung and the membrane attack complexes C5-9. Additionally, we will study the structural features of the cytolytic T cells and their interactions with the target tumor cells, as it pertains to their cytolytic granule content. These projects are NIH funded grants. Fulfillment of these research projects will be greatly enhanced by availability of the TEM requested. We also hope to obtain new information regarding the stoichiometry of C5-C5 convertase interactions and of the C5-C9 complex formation. Ultimate goal of all our research is to obtain data to provide useful information that can ultimately lead to development of preventive and therapeutic modes.